Lecture 5 Flashcards
What saccade test is good for baseline in sports/concussions
KD
Describe KD test
First pt looks at numbers connected by solid lines. Horizontal
Then pt looks at numbers with no connected lines. A little harder. Horizontal.
Then pt looks at numbers with no connected lines and squished together.
How to grade KD tests
Check average time and average errors by age for test 1, 2, and 3. Then find the Z score and compare to percentile rank table.
How to calculate Z score
Actual-mean
__________
Standard deviation
What happens if the child’s time on the KD test is greater than the mean?
Then use the negative Z score when looking at the percentile rank table
What happens if the child’s time on the KD test is less than the mean?
Use positive Z score when looking at the percentile rank table
DEM test what does it look like
A and B are vertical
C is horizontal and squished.
How to score DEM
Convert these to Z scores:
total vertical time. Add A and B together
Horizontal time (adjusted for omissions and additions)
Errors
Ratio of horizontal adjusted time/vertical
Compare time to the age based table.
Ages that can do DEM
6-14
How to calculate horizontal time adjusted
Adjusted time= time x 80/80 - omissions + add
80 is the amount of numbers in test
time is how long it took child to read.
How to calculate ratio for DEM
Adjusted horizontal/vertical
Type 1 DEM
Vertical:
Horizontal:
Ratio:
Normal
Normal
Normal
Results: Normal
Type II DEM
Vertical:
Horizontal:
Ratio:
Normal
High- slower than avg
Abnormal- high
Result: Ocular motor disfunction.
Type III DEM
Vertical:
Horizontal:
Ratio:
High
High
Normal
Result: RAN problem. Rapid automatic naming.
Type IV DEM
Vertical:
Horizontal:
Ratio:
High
High
Abnormal
OMD/RAN problem
How to treat OMD
VT
How to treat RAN
Speech language therapy
What is the readalyzer
Computer program that records eye movements while pt reads passage. Comprehension is tested. Compares variables to grade level norms.
What does the reanalyzer show
Fixation Regressions Fixation duration Reading rate Grade level Correct comprehensive answers
Right eye test
Eye tracking without goggles. Readout of saccades and pursuits. Diagnostic and therapeutic.
3 big picture methods for saccadic testing
Paper: DEM, KD
Computer: reanalyzer, right eye
Chairside: NSUCO/maples
Static ret
Control accommodation by cyclo, fog, distance fixation to determine distance ret
Dynamic ret
Dose not control accommodation. Purpose is to determine near rx
What percentage of cyclo to use on infants and then kids 12 months plus
Infants: 0.5%
12 moths +: 1%
Use loose lenses or skiascopy bars
Mohindra near ret
A near ret technique for assessment of distance refractive error. Static even tho not fixating in distance.
Mohindra near ret technique
Dark room without ambient light so pt will only look at ret light
Infant fixates at ret 50cm
Use skiascopy bars
subtract -1.25D from result
Toddler/preschool ret and phoropter
Use interesting fixation target- movie maybe
Pt will be too small for phoropter- do trial frame.
Do not do JCC
At what age can you use phoropter and JCC
school age. 8+
Normal refractive error for full term newborns
On average, +2.00
88% between plano and +4.00
Standard dev of 2.75
Emmetropization
Tendency for the refractive state of the eye to change close to plano. Converges to low hyperopia (+0.50 to -1.00 with S.D of +/- 1.00)
Refractive error trend
Skewed towards hyperopia
Active emmetropization
Regulated by regnal image- eye interprets retinal blur and adjusts by changing axial length. Lets longer for myopes, shorter for hyperopes.
passive emmetropization
Occurs as a result of physical/genetic changes.
physical: refractive errors move to emmetropia initially. Genetics: -Both parents myopia 42% -1 parent myopia 23% -Neither myopia 8%
Other: Changes in corneal/lenticular power.
NO active growth changes.
Emmetropization structural changes
Cyrsalline lens: Thins in infancy and early school years
Corneal power decreases
Axial growth
Berkely infant biometry study (BIBS)
What was their finding?
Emmetropization (plano to +2.00D) within 3-9 months.
Bidirectional.
Myopes will become more plus
Hyperopes will become more minus
Best predictor: Cyclo refraction
1.00D or more of cyl in __% of newborns
30%
Highest in first 2 years, adult levels by 4-5 years.
Will decrease!
If little astigmatisms in 1st year of life you can predict
That they will likely not develop any
Trend of ATR and WTR astigmatisms in infants
ATR has steady decline
WTR has uptick around 1 year and then steady decline
After age 5, what kind of astigmatism is most common?
WTR
Multi ethnic pediatric eye disease study (MEPEDS)
Looks at astigmatism in children ages 6-72 months
Greater than 1.50 DC= 16.8% hispanic
Greater than 3.00 DC= 2.9% hispanic
Most WTF, decreases with age
Lowest prevalence of myopia is in ___ year olds
5-7 year olds.
5-6 year olds with plano to +0.25 D likely to become
Myopic by teenage years. Females earlier than males.
Refractive error changes faster in children with ___ than ___
Myopia than hyperopia
Accommodation. How does it work
Ciliary muscles contract (stand up) and zonules relax. The lens becomes rounder/more convex
Development of accommodation
Occurs between ages 1-3 months, then adult like.
Infants under 3 months old, they tend to over accommodate.
Due to?
Target proximity
Large depth of field- very small pupils
Poor sympathetic innervation to ciliary muscle- to relax accommodation. q
How to test accommodation in infants/toddlers/preschoolers
Near ret
How to test accom in school age and beyond
Amp of accommodation (monocular)
- Push up
- Pull away
- Minus lens test
FCC testing
Near Ret
NRA/PRA
Done wearing correction!!
Minus lens procedure to measure accom
Done in phoropter
use 1 line above best VA at 40cm.
Add minus lenses until pt reports first slight sustained blur- not blur out.
With young children, start with -3.00D over Rx since they have a large amount of accommodation. Take diff from Rx until blur then subtract working distance.
Hofstetter’s norms
Average amp calculation: 18.5- (1/3)(age)
Minimum amp calculation: 15 -(1/4)(age) ** Sweedish study says subtract 2 from this and that it is an over estimation.
